Sighting attachment for electric semaphore lamps



June 24, 1930. s. M. DAY 1,765,865

SIGHTING ATTACHMENT FOR ELECTRIC SEMAPHORE LAMPS Original Filed March 14, 1923 2 Shets-Sheet l FIGI s. M. DAY 1,765,865

SIGHTING ATTACHMENT FOR ELECTRIC SEMAPHORE LAMPS June 24, 1930.

Original Filed March 14, 19215 2 Sheets-Sheet 2 Patented June 24, 1930 UNITED (STATES PATENT OFFICE SALISBURY M. DAY, OF ROCHESTER, NEW YORK, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY, OF GATES, NEW YORK, A CORPORATION OF NEW YORK SIGHTING ATTACHMENT FOR ELECTRIC SEMAPHORE LAMPS Application filed March 14, 1923, Serial No. 624,989. Renewed December 4, 1926.

This invention relates to detachable sighting devices for the lamp units of railway signals, more particularly to such a sighting device for the lamp unit of a semaphore signal.

In railway signaling, it is important that the indication afforded by a colored light l llollld be clearly visible and easily discerned by the engineer of an approaching train,

whether this color indication be the night indication of a semaphore signal or both the day and night indication of a day light color light signal. In the interests of economy and efficiency, it is desirable to maintain the 5 colored light in a relatively Well defined pencil or beam; and when this is done, it is highly important that this beam of light be directed in the proper direction down the track so as to be observable by the engineer :0 of an approaching train to the best advantage. I

In the semaphore signal now most genera ly used, the roundels or color screens in the spectacle are not designed to have any particular light directing or concentrating properties, being intended to act as color screens or filters. The lamp unit behind the spectacle, therefore, determines to a large extent the direction of the .colored beam of light,

and it is desirable to have the adjustment of this lamp unit correct to afford the most effective and arrestive indication. For this reason, it has been the practice to support the lamp unit behind the semaphore spectacle on an adjustable bracket, so that this lamp unit may be turned, independently of the spec'- tacle, so as to project the beam of light in the desired direct-ion. Similar adjustability is ordinarily provided for day light color light signals.

The adjustment of the lamp units of semaphore signals or color light signals, as ordinarily practiced, is a tedious and u ually unsatisfactory procedure. As a rule, one man is stationed at a distance from the signal to tell by the appearance of the signal when the best adjustment has been made, and another man at the signal itself makes the various adjustments in obedience to instructions 50 from the distant man communicated by'hand signaling. Unless the man on the track is careful to place himself in the proper posi tion and makes due allowance for the fact that the engineer of a locomotive cabis at some distance above the track, this procedure is liable to give unsatisfactory results.

With these and other considerations in mind, one of the primary objects of the present invention is to provide a simple and effective means by which a maintainer at the signal, while making any adjustment that may be necessary, can ascertain the direction in which the signal will project its beam of light and can determine when the adjustment has been made which will make the signal visible to the engineer on an approaching train to the best advantage. Generally speaking, the desired end is accomplished by providing a simple and yet accurate and dependable sighting device, which can be easily and quickly attached to and detached from, the casing of the lamp unit or light signal, and which permits one at the signal to determine the direction in which the light beam of that particular signal will be projected along the track, so that, in combination with a suitable adjustable support, the lamp unit or light signal may be accurately adjusted by one operator in the simplest and most effective fashion. By reason of the ease and facility with which such adjustment can be made, it is possible as a practical proposition to maintain the signals on a railway in the most eificient condition.

Other objects, purposes, and characteristic features of the invention will be in part apparent and in part pointed out as the description progresses.

In the accompanying drawings, Figure 1 shows a lamp unit of typical construction for semaphore signals and the adjustable bracket for supporting said lamp unit on the signal pole, together with a sighting device detachably supported on the lamp unit in accordance with the present invention;

Fig. 2 is a vertical section on the line 2-2, in Fig. 1, viewed in the direction of the arrows;

Fig. 3 is a fragmentary section on the line 100 in Fig. 1, lo oking in the direction of the arrows;

Fig. 4 is a side elevation of the lamp unit, parts being-broken away on a vertical plane through the axis of the unit, together with a side view of the sighting device;

Fig. 5 is a fragmentary view of a semaphore signal of the typical construction and illustrates the relation of the sighting device to the semaphore spectacle; and

Fig. 6 shows diagrammatically a modified form of the field finder of the sighting device.

For the purpose of disclosing the nature of the present invention, there has been shown atypical application to a semaphore signal of the ordinary construction using an electric lamp; but it should be understood that the invention is not limited to this specific application. Referring to the accompanying drawings, the semaphore lamp unit is adjustably supported on the signal pole 1 by a lamp bracket of the usual construction. This lamp bracket as a whole consists of a clamp member 2, which is firmly clamped to. the signal pole 1 by a U-bolt 3 in the usual way. The clamp member 2 is formed with square pockets to receive the heads of bolts 4 and 5, which adj ustably fasten a supporting arm 6.. The bolt 4 passes through a hole in the arm 6, while the bolt 5 passes through a slot 7 in said arm (see Fig. 2). By reason of this construction, the arm 6 may be swung back and forth to a limited extent on the bolt 4 as a'pivot and be locked in position. An angle bracket or lamp holder 8 is adjustably fastened to the arm 6 in a similar manner by two bolts 9 and 10, the bolt 10 passing through a slot 11 in said angle bracket 8 (see Fig. 3).

The casing C of the lamp unit shown has the general form illustrated, with a rounded top, a lens opening in the front, a door at the back, and a groove or pocket 12 in one side to receive the upright portion of the bracket 8. Lugs 13 integral with the casing surround said upright portion of the bracket 8, except for a space through which may pass the integral projection 8*} on the upper end of said portion. The arrangement just described makes it impossible to set the casing C of the lamp unit on the bracket 8 except in one way. A In 14, integral with the bottom of the easing is formed wit-h a V-shaped notch therem to receive a short beveled extension 8 on the bracket 8, thereby positioning the lamp unit in a definite relation with respect to the bracket 8. A set screw 15, with the usual lock nut, projects from the inside of the casing C against the bracket 8 and holds said casing firmly in place.

The rear end of the casing C is closed by bolic mirrors or reflectors.

\ As a typical illustration, there has been shown the so-called doublet combination. In this arrangement, referring to Fig. 4, there is an outer lens 18 and'an inner lens 19 of different diameters and with different arrangements of steps, as shown. These two lenses 18 and 19 are held in a lens-barrel 20 secured in an opening in the front wall of the casing C. The electric lamp 21, which may have a double filament shown, or a single filament, is mounted in a bayonet type socket or the like which is adjustably fastened to a supporting member 22 connected to the lens barrel 20. Various details of construction of this lamp unit, including modifications or adaptations of the particular arrangement illustrated, are not material to the present invention and need not be discussed. The feature of the lamp unit pertinent to the present invention is that it emits a relatively well defined beam of light along a certain axis determined by the lenses 18 and 19. Also, the lenses 18 and 19 have a definite relation to the casing C, the lens barrel 20 and shown in Figs. 1 and 4, comprises a cylindrical barrel 25, a' front leg 26 and a bifurcated rear leg 27. In one end of the barrel 25 is a small sighting opening 28; and in the other end of this barrel is a glass 29 with suitable marks thereon to define a definite line of sight. This glass 29 is held in place by a bezel ring and small screws in the usual way. In one form, as shown in Fig. 1, a small ring is sand blasted on this glass 29, leaving a small clear circle and an outer clear circle. Upon looking through the sighting opening or peep hole 28, a comparatively large field may be observed through the outside clear ring (the proportions in Fig. 1 being somewhat exaggerated), and a comparatively small field may be observed through the inner clear circle. In the other form shown in Fig. 6, the glass 29 is provided with opaque cross marks or cross hairs 30, this glass being clear or sand blasted as desired. With either of these constructions, it will be observed that the sighting device S has a definite line of sight and may be accurately lined up with a selected point or object on the trackway.

In accordance with this invention, it is contemplated that this .sighting device S and the signal casing will be so constructed or adapted that, with the sighting device in place, its line of sight will have a certain relation to the axes of the lenses 18 and 19. For ordinary purposes, the sighting device S defines a line of sight substantially parallel to the axis of the lenses 18 or 19, that is, the axis of the beam of light that will be projected from the lamp unit when accurately focused. The various signal casings C are of course manufactured so that the same sighting device S may be used on any one of them with the same result. While this support or connection between the sighting device S and the casing C may be afforded in various manners, in the construction shown, two projections or pads 31 are formed on the top of the casing C, and these pads 31 are accurately machined with the aid of suitable tools to have a definite relation to the lenses 18 and 19. If,'as previously stated, the lens barrel 20 is accurately made, the pads 31 may be machined with respect to the finished surfaces around the front opening in the casing C. I

The pads 31 are spaced to fit closely with the notched lower ends of the bifurcations of the-rear leg 27 of the sighting device. The front leg 26 of the sighting device S has a hole in its lower end which fits snugly over a pin 32 fastened to the top of the casing C in a predetermined relation to the lenses 18 and 19. This construction just described affords a stable three-point support for the sighting device S; and with the pads 31 and the pins 32 with the same spacing and in the same definite relation to the lenses of all of the signals, it will be readily seen'that the same sighting device S can be applied to any one of these signals and will accurately define a line of sight corresponding with the direction in which the beam of light of that particular signal will be projected when its lamp is on focus. In orderto hold the sighting device S firmly in place, a spring 33 is preferably used, one end .being attached to the sighting device at about the middle, and the other end having a hook shaped to be attached to the staple 34, commonly used in connection with the hasp to lock the casing. Obviously, however, clamps, screws or the like may be employed to hold the sighting device S in place if desired.

The particular shape and manner-of mounting of the sighting device S, asshown in Figs. 1 and 4, has been designed with a view of adapting it for use in connection with the lamp units of semaphore signals. The typical shape of a semaphore spectacle. and its relation to the lamp unit is shown in Fig. 5, and it will be observed that, with the semaphore in the horizontal or stop osition, there is a clear vision through the slghting device above the spectacle.

The use of the sighting device to carry out the purposes of this invention requires little explanation. The sighting device. is attached to the casing C of the lamp unit in a manner which will be evident, the legs 26 and 27 of the sighting device being such that it can not be misplaced carelessly or accidently. With the sighting device thus positioned, and with the semaphore signal in the horizontal position, as shown in Fig. 5, the maintainer by looking at the sighting device can see where the axis of the beam of light would fall if the light were lighted (observations being ordinarily carried on to better advantage in the day time than at night) By this observation the engineer can ascertain if the lamp unit isproperly adjusted, he having probably picked out some distinctive object or point along the track previously where the axis of the beam of light should fall in order to makethe indication of the signal visible by the engineer of an approaching train to the best advantage, due allowance being made of course for the grade, curvature in the track, and the distance the engineer is above the track when riding in the cab. If the observation through the sighting device shows that this articular lamp unit is not pointed in the right direction, by loosening the nuts on the bolts 4 and 5 the lamp unit may be tilted forward or backward, and loosening the nuts on the bolts 9 and 10 said unit maybe swung in either direction on a vertical axis. Such movements in different vertical planes obviously permit the lamp to be used in any desired direction, within the limits afforded by the length of the slots 7 and 11. If necessary, the clamp member 2 may be raised or lowered or turned on the pole. In any event, the maintalner may shlft the lamp unit in any direction and by repeated observations through the sighting. device and trial adjustments may bring the beam of light which the lamp u-nit wou ld pro ect so' that it points in the proper d1rect1on.

From the foregoing it will be readlly appreciated that this invention provides a s mple and effective way of ad usting or checking u the adjustment of the lamp units of semapliore signals or the units of color l ght signals or light projecting devices. This is a great advantage under practlcal operating conditions on railroads for varlous reasons. It permits routine inspections, and facilitates installation or replacement of llght pro ect ing units in many respects. It 1s of course essential to the success of the invention to have a predetermined and definite relatlon between the sighting device and the light possible to make inspections or adjustments of any signal in the simplest and most direct manner.

The sighting device S heretofore explained has reference more particularly to getting the light projecting unit pointed 1n the proper direction; and it is assumed that the electric lamp or other source of light Wlll be accurately focused with respect to the lenses,

1o reflectors, or the like. In .the particular type of lamp unit shown, the lamp receptacle 1s adjustably supported from the member 22 having a definite relation to the lenses 18 and 19. When originally assembling the signal, or upon replacing a burned out lamp, the receptacle for the amp may be ad usted with respect to the signal to bring the filament of the lamp then in place in the proper relation to the lenses 18 and 19, suitable focusing de- 20 vices being preferably used in performing this operation. Or, the lamp receptacle may be adjusted during manufacture to have a certain definite relation to the lenses, and then the several lamps used in the signal may be rebased so that, when inserted in this receptacle, their respective filaments will come at the desired point with relation to the lenses. These and various other optical features of the light projecting unit are suscepao tible of variation in practice in connection with this invention; and while the particular arrangement shown is found to meet all satisfactory requirements, it should be understood that many variations and adaptations 85 may be made in this particular arrangement without departin from the invention.

In order to ma e clear the nature of this invention, there has been shown one specific embodiment thereof, including one particular structure of sighting device S, and one particular form of cooperating means associated with this sighting device and the easing of the lamp unit to establish the desired relationship between said sighting device be understood that the particular form, shape and portion of the parts shown and described are merely illustrative, and that various substitutions, adaptations, and modifications may be made in the particular construction and arrangement of parts shown and described without deviating from the invention, the scope of which is pointed out in the appended claims.

What is desired to be secured by Letters Patent of the United States, is

1. In a signal system for railways, the combination with a lamp unit comprising, a casing, a light concentrating device associated wlth said casing emitting a well defined light beam from a source of light in said casin a sighting device having three legs the ends of which have a definite relation with a line of vision defined by said device, and surfaces 65 on sa1d casing forming a counterpart to the and the lenses of the lamp unit; but it should three legs of the sightin device and having a relation to the axis of t e light beam emitted so that the line of vision defined by said sighting device is substantially parallel to the axis of the emitted light beam.

2. A sighting device adapted to be attached to the casings of railway signal light units for properly directing them alon the track way, comprising, a hollow mem er having spaced apertures definin a sighting line of vision therethrough, an supporting means for said member adapted to form'a threepoint contact with finished surfaces of the casing of a signal to be adjusted.

3. A device for properly lining up signals emitting a well defined light beam along the trackway of railroads comprising, a hollow member having a small opening in one end thereof, means in the other end of said member to define both a large and a small field of vision, and means associated with said member for yieldingly urging it in engagement with a standardized signal casing in a manner so that the line of vision through said member is substantially parallel to the axis of the light beam.

4. In a signal system for railroads, the combination of a lamp casing having means associated therewith for emitting a well defined beam of light for giving a distinctive signal indication along the trackway, three bearing portions on said casing having a predetermined relation to the light beam emitted from said casing, a sighting device comprising means for defining a line of vision and having three bearing portions located to have a predetermined relation with said line of vision, the relation of the several parts being such that when the bearing portions of the sighting device are placed in operative relation with the bearing portions of the signal casing the line of vision through the sighting device and the axis of the light beam are substantially parallel.

5. In a signaling system for railways, a signal light casing for a semaphore spectacle having means for emitting a concentrated beam of light, finished surfaces on said casing having a predetermined relation to said beam of light, and a detachable sighting device having three legs, the ends of which have a definite relation with a line of vision defined by said device, said legs being arranged to engage said finished surfaces on said casing whereby when said sighting device is attached to said casing there is a predetermined relation between said beam of light and the line of vision of said device.

6. In railway signaling apparatus, a light projecting unit comprising, a casing carrying a light source and means for projecting a concentrated beam of light from said source, three spaced surfaces on said casing, said surfaces being arranged in a predetermined relation to said beam of light, and a sighting delight.

signature.

In testimony whereof I hereby aflix my SALISBURY M. DAY. 

